Pleuro-Pneumonia of Cattle. 165 



sterile, and the rabbits remained healthy. There were confined 

 in the sacs containing the opalescent medium no bacteria cap- 

 able of cultivation on the ordinary laboratory media. Under 

 microscopic examination, with a high magnification (1500-2000 

 diameters), and with an abundant illumination, there was ob- 

 served in the opalescent culture medium a number of very small 

 and refringent points, so small that their individual structure, 

 could not be accurately determined. 



Shortly after the discovery of the causal organism of con- 

 tagious bovine pleuro-pneumonia by Nocard and Roux, the 

 disease engaged the attention of a number of scientists in vari- 

 ous parts of the world. In 1900 Dujardin-Beaumetz (6) pub- 

 lished his thesis on the isolation and cultivation of the organism 

 discovered by Nocard and Roux, which he showed could be 

 grown in vitro in a special medium, consisting of Martin's pep- 

 tone bouillon, with the addition of serum. The organism was 

 -capable of traversing Berkfeld and Chamberland F. filter candles 

 provided the virus or culture was suitably diluted prior to fil-' 

 tration. On the contrary, the Chamberlain B. filter candles 

 formed an impassable barrier to the organism, irrespective of the 

 •dilution employed. He also described the characters of the cul- 

 ture in special broth, and on solid media, and was able to pro- 

 voke in cattle, by subcutaneous inoculation of pure culture in 

 the trunk, a typical oedematous engorgement corresponding in 

 .all its appearances to that following the inoculation of lung virus 

 into similar animals in similar situations. 



In 1906 Dujardin-Beaumetz (7) succeeded in producing, with 

 pure cultures of the organism in broth plus sheep's serum, and 

 in broth plus horse serum, similar lesions in sheep and goats 

 to those observed following the inoculation of culture in broth 

 plus ox serum into cattle. 



In 1910, Borrel, Dujardin-Beaumetz, Jeantet, and Jouan (4) 

 -described in detail the morphology of the organisms they had 

 isolated from pure cultures. They remarked upon the poly- 

 morphism of the organisms in the preparations examined and 

 ■described filamentous forms, chains, granules, round forms, ovoid 

 forms, and pseudo-vibrion filaments. Asteroid forms in par- 

 ticular were described, and they suggested the name " Asterococ- 

 <cus mycoides " for the organism. 



Bordet, in 1910 (2), also published the result of his observa- 

 tions concerning the morphology of the organism of contagious 

 pleuro-pneumonia. He described granules and filaments re- 



